In a nutshell: Several areas of the brain involved in processing visual information respond differently depending on whether an object is in an expected or an unexpected location.

Our brains use incidental learning to take in sensory information throughout everyday life. This helps us to adapt to predictable patterns, so that we can respond appropriately when stimuli or situations match what we have previously encountered – that is, when they fulfil our expectations. For example, seeing a mailbox in front of a house would be consistent with most people’s expectations, but seeing a piano in a forest would violate our expectations, because it is not something we would typically experience.

Previous studies have looked at specific brain regions to study their involvement in incidental learning. Brain Function CoE researchers Michelle Hall, Jason Mattingley and Paul Dux at the University of Queensland used a more general approach to investigate the brain’s sensitivity to violations and fulfillments of expectations.

The researchers used an incidental learning task in which the locations of specific objects were manipulated without participants’ knowledge. Participants identified colourful kaleidoscope pictures on a computer screen. Each picture appeared most often in a specific location, and only occasionally in a different location. The researchers used brain imaging to record patterns of activity across the whole brain.

In some brain regions, the pattern of brain activity was more consistent when participants viewed shapes in an expected location and more variable when participants viewed shapes in a surprising location. However, in other brain regions, the opposite effect was found.

These opposing results suggest that expectations are processed differently across the brain, depending on whether they are violated or fulfilled. This research helps us to understand how the brain makes sense of the surprising and unsurprising things that we see, and which parts of the brain are involved.

Next steps:The team is interested in whether the brain responds to things that occur at surprising times in a similar way as it responds to things in surprising places.